Idina Menzel, who has crossed over from the Broadway stage to the Billboard charts, is still surprised that she’s able to sell concert tickets like a proper pop star. Menzel said in a recent interview, “It’s hard to cross over like that and that’s what this whole last year has been about for me. The 44-year-old will kick off a North American tour Tuesday in Richmond, Virginia. The tour will feature music from her career, including songs from Broadway shows like “Wicked” and “If/Then,” and the animated hit “Frozen.” “Frozen” includes the Oscar- and Grammy-winning song “Let It Go,” which peaked at No. 5 on the Billboard Hot 100 chart.